Improvement in molding for metal castings



J.P.BR0ADMBAD0W[ MOLDING POR METAL CASTING IPantenfed-Nov. 29,

NTTED STATES y, PATENT l Ormes.

HiMsnLF AND ALBEiT EAMns, OF SAME PLACE.

iMPRovEMENT IN MoLDlNG FOR.Ivilai-.ALVCASTINes.`

Specification forming part of Letters Patent N0. 26,321, datedNovember 29, 1859. v

.To all whom it may concern:

Be it known that I, JOHN P. BROADMEADOW, of Bridgeport, in the county of Fairfield and State of Connecticut, have made certain new V and useful Improvements in FoundryMachinery; and I do hereby declare that thefollowing is a full, clear, and exact description of the same, reference being had to the aecompanying drawings, which form part of this specification, and in which- Figure l represents a front elevation of the press used by me in practicing my` invention. Fig. 2 is a sideelevatiou of the same, and Fig. 3 represents a vertical transverse section through the center of the same. Fig. 4 represents avertical longitudinal section of a cope ofthe flask, patterns and their appurtenances, and the sand ready for pressing. Fig. 5 is a plan of the cope-plate, and Fig. 6 is a plan of the cope and patterns. Fig. 7 is a side view of the strike. Fig. 8 represents a vertical longitudinal section of the drag of the flask, the patterns and their appurtenances ready for pressing. Fig. 9 is a plan of the bottom plate, and Fig. l0 is a plan of the drag and patterns. Fig. 1l. represents a vertical longitudinal section of a complete mold ready for pouring. Fig. l2 represents a vertical longitudinal section of a drag, pattern, and their appurtenances; and Fig. 13 is a plan of the drag and pattern.

My invention relates to the formation of sand molds for casting by means of mechanical devices, so as to supersede the handlabor usually required in rammin g the sand; and it has reference particularly to what is technically called snap-fiask molding, or the formation of sand molds in flasks so constructed that they are removable from the molds before the metal is poured in. The advantages of this kindofmold-` in g for small articles havelong been known, as it permits a number of molds to be formed by the use of a single fiask, and my improvements enable the molds to be formed with greater precision and with much less labor than has heretoforebeen possible, thus insuring better castings at aless cost.

Before proceeding to describe my improvements it is proper to state that YI do not pretend to be the first that has substituted mechanical pressure for hand-ramming in the formation of sand molds, nor to be the origi-w 1 nator of snap-flask molding; butI believe that` y I have so simplified the machinery "andVpo-y` cess of sand-molding by machinery as to` reii-` der it practically valuable for ordinary fdunf" dry purposes.

My invention by whichthis result `is" at-` tained is divided into several parts, `the list` part of which consists in the combined seof; l a half-flask of sufficient sine `to. contain? the quantity of loose sand required to form a half#` mold, with afolloW-boardsmall enoiigh to enter freely into the said half-.flask and actas a l .l piston to compress thesand whenproper press.` 1 l ure is applied,.so that the half-flask not only.. y performs the usual duty of containing the rammed sand or mold,but also acts asa measy.` ure to determine the quantity of loose Sandi which is to be rammedor pressed. Thispart of my invention possesses an advantage over 1 y preceding inventions in mechanical sand-u molding-such, for example, asthat of Ghapf@` man Varner-in dispensing with the use of al; hopper or other measure ofthesand separate; j from the flask, and consequently permits the] 1 J molding to be accomplished with greater speed and less complex mechanism.

The special object of the second part of inly 1 invention is to insure thelequable-ramming 3 or pressing of thesand by the operation of the follow-board; and.A it consists in the eorn-` j l p bined use of astrike whose profile is sul` stan`` tially the same as that of the pattern, and of the half-fiask above described, so that by the i. Operation of the former definite portions of f the loose sand in the lattercan be removed from above the protuberant `portions of the@ patterns previous tocompression.

The special object of the third part of` my'f` invention is to insure the retention of the sand in the cope of the ilask when it is lifted from the match-board; and it consists inthe coinl 1 bined use of a ribbed cope-.plate of the half- `l .flask that constitutes the cope, and of pins` in the said cope that sustain thecope-plate,`

the said cope-plate beingfsmall enough to enter into the cope, so `thatthe weight of l the sand adhering to theribs ofthe cope-plateg when the latter is depressed intothe `flaskis` transferred by the sustaining-pins to the cope.

The special object of the fourth part of my l n invention is to insure the integrity ot' theV mold (after the snap-flask is removed) during the pouring of the metal; and it consists in the combined use of a bottom plate of a size to pass into the lower half-liask, or drag,77 as it is technically termed, of the aforesaid cope-plate, and of clamps that connect the cope-plate and bottom plate together after the snap-flask is removed. This part of my invention dispenses with the employmentof the `weights generally used in snap-flask molding ytern and permit its descent when the pressure is applied.

The special object of the sixth part of my invention is to insure the equable Acompression nof the sand of the mold in articles of such a form that a profile-strike cannot be employed with advantage; and it consists in the combined use of a follow-board having suitable projections or depressions, or both, thereupon, in connection with a plain half-flask, by which I mean one with straight sides, such as above specified, in contradistinction to the plans previously in use, in which the half-flask is furnished with projections or indent-ations. This part of my invention is important, as it permits the application of mechanical molding to a great variety of objects which cannot be molded by the use ol' the flasks having projections and depressions, hitherto used in mechanical molding.

The accompanying drawings illustrate my invention. In carrying it into effect I am enabled, from the nature of my improvements, to make use of a simple lever-press, which, although not possessing any special novelty, is, from its simplicity, admirably adapted to foundry purposes. In this press the headpla-te A is connected with the frame B of the press by means ot' a pair of standards, C C. The frame sustains the movable platen D, which is secured to the upper end ot' a pair of slides, E E, that move in suitable guides formed in the cross-beams ofthe frame. The platen bears upon a strut, F, vwhose lower end rests upon a ball formed on the outer extremity of the arm G. This arm projects from a rock-shaft, H, that extends through and is supported by the standards of the frame B of the press, and has a lever-handle, I, secured to one of its outer ends, the arrangement of the whole being such that when the leverliandleT is drawn forward the platen D is caused to approach the head-plate A. The

frame B of the press has a pair of ways, J J, secured to it, which extend on either side of the platen D, and a carriage, K, is constructed to slide to and fro on these Ways, so that objects placed thereon may be entered between the platen and the head-plate and may be withdrawn therefrom.

The flasks which I prefer to use are snaptlasks made in two halves or parts-a cope, L,

and adrag, M-each being constructed with a hinge, a, at one corner and a latch, b, at .the diagonallyopposite corner. Each of these half-flasks is of sufficient capacity to hold the quantity of loose sand required to form ahalf mold. The two halves are fitted with guidepins and holes in the usual manner, so that they may be applied exactly to each other when the two halves ofthe mold are put together.

Vhen an article similar to a roller is to be molded, the pattern is made in two halves in the usual manner, and each one of these halves is secured to a match-plate which forms the base on which the sand is compressed. The match-plate N, that is to be used in connection with the cope L, is furnished with holes similar to those in the drag to receive the guidepins ofthe cope. The match-plate O, that is to be used in connection with the drag M, is furnished with guide-pins similar to those ofthe cope L. The\drag match-plate has also secured to it the pattern c of the gates, through which the melted metal passes into the molds from the sprue. The drag is used in connection with a follow-board, P, (battened on its upper side,) of such size as to pass easily into it, so as to actas a piston and compress the sand. The cope is also used in connection with a follow-board, R, similar to the dra-g follow-board, ot' sufficient size to pass easily into the cope, and fitted with the spru epattern S, which is made fast to it. The cope match-board N is perforated to permit the end of this spruc-pattern to pass through, shown in section at Figs. 3 and 4. Both match boands are furnished with battens, which are fitted to cnter into the frame of the carriage K of the press, so as to'hold the matchboard in place. y

A cope-plate is used in connection with the cope L. This cope-plate f has a series of bars, c c, extending from that one of its faces which is next the sand. The cope L, moreover, is fitted with lateral sustaining-pins z', in such positions that when the sand is compressed by the forcing down of the cope-plate the latter rests upon these pins. A bottom plate, g, is used in connection with the drag, and when articles similar to rollers, or, in other words, that extend in lineeither across or lengthwise with the flask, are used, a strike, T, having a profile similar to that ofthe pattern is prepared.

Vhen the flasks, patterns, Src., have been prepared as above described, molding is effected in the following manner: The matchboard N of one of the parts of the tlask-the profile edge of the strike is then drawn across the surfaceof the sand to remove portions thereof over the two patterns. The operator now applies the cope-plate f, which should have been previously brushed with clay-water to make the sand adhere, and lastly applies the fol1owboard R, entering the sprue-pattern S in the hole of the match-board. He then shoves the prcsscarriage, with the flask and its appurtenances, beneath the head-plate A,

and, applying his hand to the lever-handle l, forcestheplateupward. Theplateminrising, passes through the carriage-frame and bears against the battons of the match-board, raising it with the flask and appurtenances, and bringing the follow-board R in contact with the head-plate of the press. The pressure produced by the continued movement of the lever-handle forces the cope-plate and followboard to enter into the cope, thus compressing the sand therein. Themovement of the leverhandle is continued until the copeplate reaches the sustaining-pins, which is easily known by the position of the follow-board, after which the lever-handle is let back, thus permitting the platen `to descend and drop the matchl board, with the flask, &c., upon the carriage. The latter' is now drawn forward, and the follow-board is rapped lightly and withdrawn.

The match-board is then rapped and thecope is lifted from it.

This voperation is effected without danger of the sand falling out, as the compressed sand adheres to and is sustained bythe bars of the cope-plate, and the latter, with the adhering sand, is carried by the cope through the invention ofthe sustaining-pins 'i i. The cope is then set on its side until the drag is molded, which is effected in the same manner. Then the d rag is reversed with its match-plate, the latter is rappcd and withdrawn, and the drag is carried to the part of the moldingfloor where the mold is to be poured. After it is set down the cope is applied to it, and if the patterns and match-boards have been properly made in the usual manner the two parts of the mold apply themselves perfectly to each other by entering the guide-pins of the cope into the holes in the drag. After the two parts of the flask are in place, the latches are loosed and the parts of the flask are opened and removed, leaving the mold between the bottom plate, g, Fig. 1l, and the cope-platef. Clamps j j are then applied to hold these two together, and are conveniently made secure by wooden wedges s, after which the mold may be poured. As soon as the snap-flask is removed its parts maybe used, in connection with the match-boards,the follow-boards, and other bottom cope-platcs, toformfnew molds, Y so that the same tlask answers for alarge num-V ber of molds.

In order to prevent any riskof the bursting@ of the mold by lateral pressure, itiseXpedi-i ent to introduce into each `part of the `flask, l before the sand Vis thrown in, a ring-plate, t, y

which embraces the mold during casting.

In the preceding description llhav'e supposed i the article to be molded to be a roller extend-Q3 y ing for sonic distance through theflask` with-,1 l y out change of sectiongiso that the profile-strike` l can be readily used.

Whcn the sections of the article at differ` ent parts of its length are different, a followthe sand.

molded is hub with `a broadilange.

thc forni of the pattern.

As articles to b'e molded present aninde-f 1 nite variety of forms, itis not possible tojfury nish a precise rule for determining theeXact form of thc strike and follow-board tolsuit alli cases that may arise; and as trial onlycande-` termine the best form, it is sufiicientto indi-` cate theprinciple of their construction, which is that they must correspond `in general form` l, If on trial of a new strike with the patterns. the sand is found to be too tightly packed over the pattern, a strike having a more protuberw, ant profile must be substituted 5 and it' the sand is found to be too loosely packed over thewpatl tern the profile of the strike is too protuberant. rlhe same is true of the follow-board.

Having thus described my apparatus, what I claim as my invention, and desire to secure by` Letters Patent, is-

l. The combined use ofa half-flask of asuf y ficient size to hold the quantity of loose sand l required to form a half-mold, and of a followboard small enough to enter the said half-ilask and actas a piston to compress thesand there inwhen pressure is applied, substantially as.`

herein set forth.

2. The combined use of a half-flask, as above described, and of a strike whoseprofile correspends inform with the transverse section or. profile of the pattern, substantially asherein` i set forth.

3. The combined `use of ahalf-lask, as above l described, constituting the; copc,.of a ribbed." cope-plate fitted to enter therein, and of sus-` taining-pins in the said cope, the whole open.l ating substantially as hereinset forth.

4. The combined useof the aforesaid cope-1. plate, of a bottom plate ttcd to enter the drag.` of the flask, and of clamps,subs`tantially as 1 herein set forth. j

5. Combining the sprue-pztttern with the foltradistinction-to constructing the a-sks with 10W-board, when this combination is used in projections and indentations. connection Withamateh-board having an open- In testimony whereof I have hereunto subing` to permit the descent of the lower end of scribed my name. the slime-pattern, substantially as herein/set JOHN P. BROADMEADOV. forth'. Vi tn esses:

' 6. The combination of projections or inden- XV. L. BENNEW, H tations, or both, with the follow-board, in conl EDWIN YV. CONKLIN. 

